docs: def configure(service, key, auth, use_syslog):
      """Perform basic configuration of Ceph."""
      add_key(service, key)
      create_key_file(service, key)
      hosts = get_ceph_nodes()
      with open('/etc/ceph/ceph.conf', 'w') as ceph_conf:
          ceph_conf.write(CEPH_CONF.format(auth=auth,
                                           keyring=_keyring_path(service),
                                           mon_hosts=",".join(map(str, hosts)),
                                           use_syslog=use_syslog))
      modprobe('rbd')